tienvg

Hi, first time posting here. I have 92 GT with an a/c problem. The a/c works, it's just that it's stuck in the defrost position. The dial that turns it on/off is also the dial to adjust where you want it to blow.It's been this way for a while. It happened when I had to get my car hoisted to plugged the tires. Not sure if this had anything to do with it. Anyway, it's getting very hot in miami without the a/c. Any ideas how to fix this? thanks..

86 5.0L

theres a vaccum line running from the tree above the brake booster and runs to a valve above the drier if its cracked or unplugged it will run on the defrost setting

PRO50SC

You most likely have a vacuum supply problem. Look under the dash to make sure the lines to the blend door control dashpots are ok and then have a look under at the pass side of the firewall. There should be 1 or 2 vacuum lines going into the pass compartment. Trace the lines and mahe sure they're hooked up in all places. there is also a vacuum canister in the pass side fenderwell that may be causing the issue as well.

tienvg

I've opened up the panel where the dial is located. There's a plug behind the dial. When I had this detached, the a/c would not work. Is this the part you're talking about? There's also 4 other wires(black,red,white,blue) that's connected to the dial also that runs through under the pax dashboard. I tried taking the wires off but it's on there pretty tight. Didn't want to force it..

PRO50SC

No, there should be a piece back there that has vacuum lines on it. For your vent selector. That's a good place to start though.

tienvg

Any idea what color it is. I have a chilton manual but couldn't find anything on it. Hope I don't make this worse..

PRO50SC

What color what is?

tienvg

The vacuum line. I'm sure you realize by now I keep mechanics in business

PRO50SC

Different colors. Can't remember, just keep nosing around.